I would have liked a contrasted example for the valid form as well. Thanks.

I think venn diagrams might be helpful to illustrate how this concept is applied.

an encouraging message that hopefully future me will send as well.

love that comic.

I think the club example is helpful in clarifying the relationship between the sufficient and necessary conditions. It is not always intuitive and takes some work, so thank you to all of you in the comments section for the helpful hints!

All Canadians like Don Cherry's suits.

John doesn't like Don Cherry's suits.

John isn't Canadian.

I think this would work...?

Conditional: subset -> superset

Contrapositive: not superset -> not subset (flip & negate)

All banking buildings are downtown.

Building A is not downtown.

Building A is not a banking building.

I got Question 3 right, but my method was off. Thanks for the clarification!

The old student rediscovered the structure of grammar and enjoyed the simple elegance of language.

truth! DOLs were something I should have been better at: Daily Oral Language exercises.

Does this work?

While a classic dessert for this holiday is pumpkin pie, I think we should get chocolate cake. Chocolate is much more popular than pumpkin and the cake decor is much prettier.

In spite of Justin Trudeau's summer campaigning efforts, the conservatives still hold a commanding lead in the polls.

TIGER:

All true LOTR fans love the integrity of the book narrative above all other versions. Amazon's "The Rings of Power", seemingly disregard the integrity of the the book narrative above their own version of the LOTR universe. Amazon's "The Rings of Power" are not beloved by true LOTR fans.

it's interesting that the test is more concerned with dissecting arguments rather than discerning the truth. I guess that is the difference between a lawyer and a philosopher.

We got this.